The present invention is concerned with presses for forming cylindrical or round bales.
These presses are of a well-known general type comprising sets of bands or belts which, by their displacement, form by rolling up inside a chamber formed in the body of the press a bale of generally cylindrical shape from harvest products, particularly forage or hay, gathered on the ground while the press is advancing. When the bale has attained the desired diameter and has been bound, the rear gate of the press is opened and the bale is ejected onto the ground. The formation of another bale by rolling up can then be commenced inside the press.
The products that are to form the bale are gathered on the ground by means of a pickup. They are transferred by the latter into the chamber of the press between the runs of the bands or belts which at the commencement of the operation occupy positions closely adjacent each other. Due to this close together positioning and to the displacement in opposite directions of the said runs of the bands or belts, the products gathered at the beginning of the formation of a bale tend to become rolled up and to form the core of a new bale, the diameter of which will progressively increase, the runs of the bands or belts moving apart from each other in accordance with this increase in the diameter of the bale. These bands or belts are then maintained under tension by tensioning rollers which are themselves subject to the action of springs or hydraulic cylinders.
In order to assist the commencement of the formation of the bale, there is provided in known manner, near the front part of the gap or opening for the entry of the products into the chamber of the press, a roller which will be termed a starting roller, near a stationary roller of the press over which the bands or belts pass and which normally serves as a driving roller.
In the case of certain harvest products, especially products which will eventually be made into forage, for example ryegrass, and especially in damp conditions, difficulties arise due to the fact that these products have a tendency to become rolled up around the conventional starting roller, which hinders the formation of a correct bale core and is besides a cause of the formation of tightly packed lumps of material which can bring about the stopping of the press and which consequently slow down the working tempo.
The object of the invention is to cure this disadvantage of the existing presses.